Big brake kits are the ultimate in performance stopping solutions, often derived from high specification competition parts, they completely replace the factory components with equipment aimed solely at achieving maximum, reliable and repeatable braking performance. For outright braking performance, bigger is always better and as such big brake kits feature the largest possible components capable of being housed inside the wheels of the car. Typically, kits will comprise of large lightweight multi-piston brake calipers, huge (often 2-piece) brake discs and appropriate performance brake pads as well as corresponding brake lines and fluid. It is also worth noting that, for certain applications, increased size brake discs are offered as a standalone upgrade usually where a car is fitted with a 4 or 6 piston caliper as standard. In this instance a 2-piece, larger diameter disc coupled with an adapter bracket, or elongated bolts and spacers can be a fantastic solution to increased braking performance.

Whilst competition standard braking systems have started to filter down through high-end, factory performance cars it’s unusual to see 6 or 8 piston calipers fitted as standard to the types of machinery you might find taking part on a track day. They are, however, a regular occurrence in big brake kits where the larger the disc the greater the number of pistons in the caliper, this allows the braking force to be distributed as evenly as possible. Often the calipers will be of lightweight, monobloc design keeping unsprung weight to a minimum and implementing the maximum possible size within the tight tolerances of the wheel and suspension. Responsible for housing the brake pads, a larger caliper will allow a bigger brake pad resulting in greater performance due to an increased surface area.

A large percentage of the increased performance on offer from big brake kits can be accredited to the upgraded brake disc – the bigger the diameter of the disc the greater its ability to absorb heat which is particularly import when it comes to track driving and the repeated hard and heavy braking zones. The drawback with bigger brake discs is increased weight, however, typically a 2-piece design is used to combat this meaning that the central ‘bell’ or hat of the disc is a separate part which will typically be machined from a lighter weight material to help offset the weight of the outer disc or ‘rotor’. This 2-piece design is bolted together in either a fixed or fully floating fashion and provides significant improvements in heat dissipation. Often there will be the option to have disc face drilled, grooved or slotted to help degas the space between the brake disc and pad improving initial bite and reducing brake fade but the biggest performance enhancement comes from directional/handed cooling vents/veins increasing airflow through the disc assembly.

Upgraded brake discs are one of the more easily achieved performance modifications for your track car, particularly if the standard brakes are worn and need replacing. Starting with direct-fit discs which are of the same dimensions as the original, enhanced performance comes in the form of an improved surface design where aftermarket options include drilled, grooved and slotted disc faces. With these products you benefit from degassing and deglazing of the brake pads as they reach extreme temperatures but also increased resistance to brake fade whilst retaining the ease of fitment inherent in components of factory dimensions. Typically, upgraded discs will be offered with a specialist surface coating that not only aid the ‘bedding-in’ of new pads to new discs but also offer corrosion resistance for parts of the disc not covered by the swept area of the brake pads.

In addition to upgrading the disc surface it is also possible to increase its size – put simply the bigger the brake disc the better the performance. A larger disc has more surface area for pad engagement and to dissipate heat, it also results in more leverage when the caliper clamps down on the outside edge. Implementation of this kind of upgrade can be achieved in several ways including swapping the original equipment for that of a higher model with a better specification brakes or installation of specialist aftermarket brake discs which often come as a kit incorporating the necessary hardware. Usually, aftermarket kits will feature high performance, 2-piece brake discs for an even more significant increase in stopping power, use of such a kit provides competition levels of braking performance whilst retaining the factory calipers. Installing enlarged brake discs on your car will require supporting modifications such as brake caliper adapters or spacers and will also be limited by the diameter of wheel being used.

Beyond this brake disc upgrades become more dedicated, race-derived products with an increased cost to reflect the more complex design or material utilised to deliver more significant performance increases. The majority of vented brake discs will be of cast-iron manufacture, which is cost effective, reliable and proven over a significant number of years use in industry but for outright performance composite discs are unrivalled. Exotic cars or high-end race applications are now commonly fitted with carbon-ceramic brakes offering maximum stopping power with minimum weight, however, as the name might suggest they are a significantly more expensive option. Not only are they the ultimate in performance they also offer exceptional durability with a significantly longer lifespan than regular braking systems and the inherent non-corrosive properties of their composite materials. The downside however is if being worked out of their temperature window, they can wear fast and leave you with a significant cost to replace.

Another common and cost-effective upgrade to a vehicles braking system is the installation of high-performance brake hoses, typically referred to as braided brake lines. Brake hoses are the flexible connection between the main body of the car and the caliper at the wheel hub and are responsible for delivering brake pressure through the flow of brake fluid back and forth. Standard factory brake hoses are usually made of durable rubber materials which not only deteriorate and perish with age but also can bulge and flex under the immense braking pressures associated with track driving.

Whilst there are now a number of performance brake line manufacturers in the industry, they all follow a very similar design and manufacture process. The proven recipe is a high specification PTFE hose inside a braided stainless-steel outer, usually covered by a customisable protective plastic coating and connected by billet, corrosion proof fittings. As a result, a braided brake hose is far less susceptible to wear, and fatigue compared to its rubberised counterpart and boasts far more positive feedback through the pedal as well as near on zero pressure loss between the brake foot and caliper. Not only does this result in improved performance and reliability it also means far greater confidence in your brakes and car control. It’s worth noting that as well as off-the-shelve solutions, custom applications are easily catered for and braided hoses can also be used in clutch hydraulic systems as well as the solution to corroded hard pipes.

If, once you’ve optimised the rest of your braking system, you’re having difficulty keeping on top of temperatures then you’ll be considering brake cooling solutions. Much like many other performance upgrades, brake cooling filters down from race car design where several forward-facing ducts channelling oncoming cooling air directly from the front of the vehicle to the braking assembly, this draws heat away from the brake disc helping to maintain a more stable operating temperature and consistent braking performance. There are model specific solutions available for brake ducts but the important part of brake ducting is ensuring that it cools the disc as a whole rather than just one side and the best method of doing so is directing the cooling air to the rear of the brake bell (the centre) so it can be centrifugally forced outwards through the veins of the ventilated disc.

Brake pad shims can also be used to prevent the damaging effects of heat within the braking system – manufactured in a number of different materials, with titanium or carbon fibre typically being the most effective, they are positioned between the brake pad and the brake caliper. The purpose of these shims is to reduce heat transfer from the pads to the caliper and the brake fluid contained within it, they also provide an extra layer of protection to the piston seals and rubber dust boots of road use calipers which often succumb to the extremes of temperature in track use.